Dietary fiber incorporation into bread dough systems greatly interferes with protein association and behavior during heating and cooling. The objective of this study was to understand the individual and combined effects of dietary fibers on dough behavior during mixing, overmixing, pasting and gelling using the Mixolab® device. Impact of different commercial dietary fibers (inulin, sugar beet fiber, pea cell wall fiber and pea hull fiber) on wheat dough mixing, pasting and gelling profiles has been investigated. Mixolab® plots indicate that the incorporation of sugar beet fiber into the dough matrix induces the disruption of the viscoelastic system yielding weaker doughs, and it greatly competes for water with starch affecting pasting and gelling. Conversely, inulin in the range tested seems to integrate into the dough increasing its stability. Additionally, the responses acquired with this device were compared with those obtained with other available methodologies, such as the Brabender Farinograph and the Rapid Visco Analyser, to explore its use as a suitable technique for studying fiber-enriched bread dough physical properties. A broad range of correlation between Mixolab® and traditional devices were found.

The stated link between the intake of dietary fiber and several health benefits [1-2] has prompted the interest in fiber enriched foods and moreover, in fiber enriched
4 baked goods. Nevertheless, the design of fiber enriched baked goods is always encountered with the consumer resistance to accept breads with reduced loaf volume and hard crumb accompanied by particular flavours [3-4].

Dietary fiber incorporation into wheat dough greatly interferes with protein association and its further aggregation during heating. Presumably, fibers occupy the space of the proteins in the gluten network [5]. In addition, fibers also affects pasting characteristics of starch such as peak viscosity, breakdown and final viscosity [6]. Moreover, the resultant ﬁber-rich doughs have high water absorption, become shorter and have reduced fermentation tolerance [5, 7-8]. Physico-chemical properties of fibers greatly vary depending on the source and the type and degree of processing [9]. Those characteristics have great impact on the functional quality of the intermediate manufacturing and end products when obtained by conventional breadmaking processes [10-11]. Therefore, it becomes necessary to assess the impact of fibers on bread dough rheology when potential use of fibers is considered for enriching baked goods.